The landscape ot the Val d'Orcia as it unfolds nowadays was created by wealthy Siennese merchants in the 14th and 15th centuries. The farms cultivate mainly grains, vines and olives. Rows of cypresses are also a distinctive sight. The beauty of the area inspired Renaissance painters and early travellers on Via Francigena.

Pienza

It was in this Tuscan town that Renaissance town-planning concepts were first put into practice after Pope Pius II decided, in 1459, to transform the look of his birthplace. He chose the architect Bernardo Rossellino, who applied the principles of his mentor, Leon Battista Alberti. This new vision of urban space was realized in the superb square known as Piazza Pio II and the buildings around it: the Piccolomini Palace, the Borgia Palace and the cathedral with its pure Renaissance exterior and an interior in the late Gothic style of south German churches.
The historic centre of Pienza represents the first application of the Renaissance humanist concept of urban design, and as such occupies a seminal position in the development of the concept of the planned 'ideal town' that was to play a significant role in subsequent urban development in ltaly and beyond. The application of this principle in Pienza, and in particular in the group of buildings around the central square, resulted in a masterpiece of human creative genius.
The leading humanist Enea Silvio Piccolomini (1405-64), elected to the papal throne in 1458 as Pius II, was born in Corsignano, situated on a hill overlooking the Orcia and Asso valley a short distance south-east of Siena. When he returned there after becoming pope, he was struck by the extreme misery of its inhabitants, which inspired him to endow his birthplace with new buildings, and make it his summer court. His vision derived to a great extent from the German-born philosopher Cardinal Nicolà Cusano. The link with the German Gothic tradition is shown by Pienza Cathedral, which the pope wanted to be in the same style as the late Gothic Hallenkirchen in Germany. To transform Corsignano Pius II called upon Bernardo di Matteo Gamberelli, known as Rossellino, ingegnere di palazzo to Pope Nicholas V in Rome, where he had been influenced by Leon Battista Alberti, the humanist thinker and architect, responsible for the restoration of Rome in 1447-55 and author of De re aedificatoria (1452), the first architectural treatise of the Renaissance.
Rossellino was responsible for the major buildings around the central square, where work began in 1459. He was also responsible for the overall layout of the town, based on the principles of Renaissance town planning enunciated by Alberti. The walled village of Corsignano consisted of a main street joining the two gates, flanked by smaller perpendicular parallel streets. Rossellino largely respected this basic structure when siting his major buildings around the main square. Pius II's project also required the building of large houses for the cardinals in his retinue, and work on these began in 1463. Two structures with a social function, the hospital and the inn in front of the church of St Francis, were also built on his orders.

The ideal centre of Pienza is the Piazza Pio II. Its trapezoid plan is emphasized by the herringbone paving edged with travertine. On the south side of the square is the cathedral (built 1459-62), designed by Rossellino. The influence of Alberti is strong in the composition of the triple facade with its wide arches, corresponding with the three-aisled interior. The interior, divided by tall clustered pilasters from which the arches and cross-vaults spring, was inspired by the Hallenkirchen. The bell tower also blends Gothic and Renaissance forms. On the west side of the Piazza is the Piccolomini Palace, built in 1463 on the site of old houses owned by the family. The front elevations, resting on a travertine plinth, are divided into three bands of sandstone ashlars, interrupted by wide arched windows. Three of the sides are the same and the fourth, with an imposing triple-tiered Ioggia, looks out on a raised garden. The fine interior courtyard is decorated with sgraffito ornamentation on the second and third floors.
The Episcopal Palace is on the opposite side of the piazza. The old Pretorio Palace was purchased in 1463 for Cardinal Rodrigo Borgia, who added an extra storey and replaced the Gothic windows. The Town Hall (1462) on the north side of the square is in conventional Tuscan style for buildings with this function, with an open loggia at ground level and a crenellated tower. In contrast with the other buildings around the square, it is in stuccoed tufa and brick, decorated with sgraffito, only the loggia in travertine.
The other major buildings in Pienza line the Corso Rossellino, most built as houses members of the papal court, although some earlier buildings survive. They include the Gothic Church of St Francis and its Convent; the Atrebatense Palace (Gothic structure with Renaissance decoration); the Ammannati Palace, in Renaissance style; the brick Palazzetto; and the Gonzaga Palace, one of the few buildings that retains its garden. Pienza has many Renaissance fountains and wells, the designed by Rossellino.
[from Historic Centre of the City of Pienza | whc.unesco.org]